Comprehensive waste treatment system and related methods for animal feeding operations to effectively recover waste solids for beneficial re-use and for treatment of wastewater for nutrient removal and recycle, re-use or discharge

Abstract

A process is provided to create a treated recycle stream through pre-treatment and solids separation for reuse in animal feeding operations without odors and creates a treated liquid effluent that can be stored for reuse, or can be land applied without odors and is free from pathogens and nutrients. Additionally the methods describe a means of converting animal manure to organic fertilizer and removing nutrients from the liquids to create a feed supplement from biomass. The organic fertilizer is non-leaching and free from pathogens. The entire process is accomplished in a reduced footprint from other treatment processes and allows waste ponds to be removed from service.

We claim:  
     
         1 . An apparatus for treatment of animal manure and wastewater, said apparatus comprising in combination: 
 a means of providing conditioned re-cycle flush water, through pretreatment and solids separation, for waste fluming;    a contaminated wastewater source connected in fluid flow communication with said means of conditioning;    a means of processing the reject material from the re-cycle flush wastewater;    whereby said reject material is treated in order that it can be re-cycled with reduced environmental impacts and/or can be beneficially re-used.    
     
     
         2 . The treatment apparatus as in  claim 1 , further comprising a mechanical screening device or a de-gritting device to remove non-fecal grit from the flush water waste stream prior to treatment of the recycle waste stream.  
     
     
         3 . The treatment apparatus as in  claim 1 , further comprising a mixed equalizing and reaction vessel device, where the wastewater re-cycle flush water is mixed with a precipitating metal-salt acid solution to maintain pH of the solution, to suppress or eliminate ammonia releases to the atmosphere (de-gassing), and to remove a portion of the soluble o-phosphate as insoluble metal-phosphate, providing coagulation to assist the liquid-solids separation that follows and to normalize down-stream flows.  
     
     
         4 . The treatment apparatus as in  claim 1 , further comprising a flocculation device, to add flocculant to the wastewater stream to increase the efficiency of the liquid/solid separation prior to re-cycle as flush water.  
     
     
         5 . The treatment apparatus as in  claim 1 , wherein the means of providing conditioned re-cycle is further described as a dissolved air flotation (OAF) device, where the flocculated manure solids are separated from the re-cycle flush water, and dissolved oxygen is added to prevent anaerobic conditions, and includes a receiving vessel for conditioned water from the DAF for return to waste fluming, which automatically reject the excess water volume from the re-cycle flush water.  
     
     
         6 . The treatment apparatus as in  claim 1 , wherein the liquid reject is further processed using a biological treatment system.  
     
     
         7 . The treatment apparatus as in  claim 1 , wherein the reject manure solids are further processed for stabilization.  
     
     
         8 . The treatment apparatus as in  claim 7 , wherein the reject manure solids are stabilized using an apparatus further described as: 
 a preconditioning device to flocculate the manure solids to allow for dewatering, said preconditioning system to be an in-line or batch process whereby a multiple chemical feed system mixes the flocculation chemicals with the reject manure solids at proper ratio;    a combination filter press vacuum drier (VFP) device, in fluid flow communication with the preconditioning device to pressure dewater the reject manure solids as they are fed into the VFP to produce a wet cake, with a filtrate return system from said VFP, wherein the liquids fraction separated in the pressure dewatering step is returned to the recycle loop and/or a biological treatment system as in  claim 14 , and the wet cake formed during the pressure dewatering phase is dried through the application of heat and vacuum, resulting in a relatively dry, disinfected organic fertilizer and the vapor water removed is re-condensed and returned to the recycle loop;    
     
     
         9 . The treatment apparatus as in  claim 6 , wherein the biomass produced is further process to produce a biomass feed or biomass fertilizer;  
     
     
         10 . The treatment apparatus as in  claim 9 , wherein the biomass solids are further processed utilizing: 
 a preconditioning device to flocculate the biomass solids to allow for dewatering, said preconditioning system to be an in-line or batch process whereby a multiple chemical feed system mixed the flocculation chemicals with the biomass at proper ratios;    a combination filter press vacuum drier (VFP) device, in fluid flow communication with the preconditioning device to pressure dewater the reject manure solids as they are fed into the VFP to produce a wet cake, with a filtrate return system from said VFP, wherein the liquids fraction separated in the pressure dewatering step is returned to the recycle loop and/or a biological treatment system as in  claim 14 , and the wet cake formed during the pressure dewatering phase is dried through the application of heat and vacuum, resulting in a relatively dry, disinfected organic fertilizer and the vapor water removed is re-condensed and returned to the recycle loop.    
     
     
         11 . The treatment apparatus as in  claim 6 , said apparatus comprising an intermittent-cycle extended aeration system (ICEAS) using a complete-mix, complete-oxidation, modified-batch process to meet discharge requirements.  
     
     
         12 . A method for controlling phosphate concentrations in the liquid wastewater treated in the biological treatment system to prevent residual in the treated effluent without inhibiting cell growth within the process stream by; 
 diverting a portion of the phosphate-free filtrate from the manure dewatering device, directly to the biological treatment unit, until the excess level of phosphate no longer show a residual in the effluent from the biological treatment system if there is residual requiring a reduction in phosphate in the biological treatment system;    increasing the acid to metal-salt concentration of the solution used in the equalization tank for pH control if there in insufficient phosphate in the feed for proper bioactivity;    operating the DAF in a manner, so that the manure float material contains a larger water ratio, as an alternative, thereby reducing phosphate residual to the biological treatment system, until the excess level of phosphate is controlled.    
     
     
         13 . A method for controlling ammonia de-gassing in flush water, or flush water conditioning for animal feeding operations consisting of: 
 use of a pH probe in the equalization mix tank;    adjusting the ratio of acid to metal-salt concentration such that a desired pH set point is achieved;    lowering the set point until ammonia is no longer being volatilized from the liquid;    maintaining this pH set point (between 6.5 and 7.5);    thereby controlling ammonia de-gassing in the flush water.    
     
     
         14 . A method for controlling odors from animal feeding operations, said method uses a dissolved air flotation unit (DAF) designed with the proper feed to circulation ratio to ensure flush water being saturated with dissolved oxygen (DO), and all sumps, and equalization vessels are sized sufficiently small, and have relatively short residency periods, such, that there will be no anaerobic breakdown of wastes to reduced sulfur compounds, organic acids or other septic type odors.